1. Field
Embodiments relate to a light emitting device.
2. Description of the Related Art
As a representative example of a light emitting device, a light emitting diode (LED) is a device which converts electricity into infrared light, visible light, etc., using characteristics of compound semiconductors. LEDs are now being applied to devices such as home appliances, remote controls, electronic signboards, displays, a variety of automatic appliances and the like and the application range thereof continues to expand.
Generally, a miniaturized LED is fabricated as a surface mount device such that it can be directly mounted on a printed circuit board (PCB). Accordingly, an LED lamp used as a display device is also developed in a surface mount device form. Such a surface mount device may substitute for a conventional lamp and is used for lighting displays, character displays, image displays and the like, rendering various colors.
As the application range of LEDs widens, brightness required for lights in daily use and lights for structural signals increases. Accordingly, it is important to increase luminosity of LEDs. Also, a semiconductor layer such as GaN grown on a heterogeneous substrate such as a sapphire board has a large quantity of crystal defects due to lattice mismatch between the substrate and the semiconductor layer, and such defects may adversely influence reliability of a light emitting device and absorb light, thus decreasing brightness of the light emitting device.